Division of Health Sciences

Grant funds study of nanotubes' effect on lungs

By Doug BoydECU News Services

Dr. Mary Jane Thomassen

GREENVILLE, N.C.
(Mar. 4, 2013)
—
An East Carolina University researcher is studying the effects of microscopic particles that are important parts of products ranging from sunscreens to sailboats but which could pose as-yet-unknown hazards to human lungs.

Dr. Mary Jane Thomassen, a scientist and professor in the division of pulmonary and critical care medicine at the Brody School of Medicine at ECU, is looking at the effects of carbon nanotubes with help from a three-year, $368,159 grant from the National Institute of Environmental Health Sciences. Her study is titled "Chronic Granulomatous Lung Inflammation Elicited by Carbon Nanotubes."

Thomassen has been studying carbon nanotubes since 2008. Smaller than 1/1000th of a millimeter, CNTs are tube-shaped fibers that have proved useful in products as varied as cosmetics, sunscreens, bicycle frames, electronics, sailboats, space shuttles and pills. They've even been used to clean up oil spills. But not much is known about any long-term hazards from inhaling nanomaterials during their manufacture or use.

The goal of Thomassen's project is to examine specific pathways in which carbon-based nanomaterials can injure the lungs.

Exposure to carbon-based nanomaterials may be occupational and occur during commercial production processes. Alternatively, people exposed to fires that contain burning diesel fuel, methane, propane or natural gas may be at risk since these fires release CNTs. For example, they were detected in air and human tissues following the Sept. 11 terrorist attacks at the World Trade Center, Thomassen said.

CNTs entering the lung are engulfed by immune cells which then send out SOS-type chemical messages that recruit more immune cells and affect other structural cells of the lung. The result can be damage to airways and difficulty breathing. Since CNTs cannot be destroyed by the immune cells, they also can clog up small airways and cause the immune cells to pile up and try to wall off the CNTs. This process causes further damage and can lead to chronic breathing problems.

Thomassen said the next step will be to look for ways to treat CNT lung disease using a mouse model. The goal is to eventually find treatments that would be beneficial in human lung disease.

Thomassen's collaborators on the study are Dr. Barbara Barna, a scientist and affiliate faculty member of the pulmonary division; Dr. Larry Dobbs, a scientist and physician in the ECU Department of Pathology and Laboratory Medicine; and Dr. Chris Wingard, a scientist and associate professor of physiology at the Brody School of Medicine.